Displacement of sulfate, sulfonate and phosphate

Reactions of organomagnesium compounds with dialkyl sulfates or alkyl sulfonates often give satisfactory yields of the products of displacement of sulfate or sulfonate. Side-reactions have been observed, but they can often be avoided for example, an excess of the sulfate or sulfonate should be used with Grignard reagents, as some is consumed by nucleophilic attack by halide ion [A]. The dialkyl sulfates are reactive, but hazardous. Toluenesulfonates (tosylates) are less reactive, but their reactions are catalysed by copper complexes the reactions of trifluoromethanesulfonates (triflates) are catalysed by nickel complexes. Reactions of Grignard reagents with secondary tosylates appear to follow an Sn2 mechanism, with inversion of configuration [43]. 

Some illustrative examples of these types of reaction are listed in Table 8.4. Others are listed in General Ref. [A], 

Reactions of organomagnesium compounds with sulfates and sulfonates 

A few reactions of hindered Grignard reagents with trimethyl phosphate have been reported [51], 

Terauchi, Y. Ohki and Y. Matsumura, Tetrahedron Lett. 31,6385 (1990). 

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